Abstract Detail

Ericaceae: Systematics, Ecology and Evolution

McElwee-Adame, Alexandra [1], Silva, Kiley [2], Buck, Ryan [3], Gonzalez-Elizondo, Socorro [4], Flores-Renteria, Lluvia [5].

Phylogenetic and Population Structure Analyses of Arbutus in North America.

The genus Arbutus (Ericaceae) exhibits intercontinental disjunction. Three species of Arbutus occur allopatrically throughout the Mediterranean Basin, with as many as nine species distributed throughout North America. Previous studies have indicated that Arbutus may form a paraphyletic group within the subfamily Arbutoideae, with species from the Mediterranean Basin being more closely related to species of other genera within Arbutoideae instead of their North American counterparts; however, this phylogeny is considered out-of-date due to the ongoing reclassification of species. Eight species of Arbutus are known to be distributed throughout mainland Mexico, with as many as five species being found in a single location (sympatric) while only one species is widely distributed (allopatric) in the Pacific Northwest of the United States. Species within Arbutus have been difficult to differentiate morphologically due to possible hybridization and lack of distinct morphological characteristics. Through the analysis of single nucleotide polymorphisms (SNPs) and morphological data, our project aims to; 1) improve our understanding of the phylogenetic relationship among the members of the genus Arbutus 2) determine if sympatric species in Mexico such as of A. xalapensis, A. bicolor, A. madrensis, A. occidentalis, and A. tessellata hybridize and 3) determine genetic structure of the only species in allopatry (A. menziesii). Samples from herbarium collections, populations in the Sierra Madre Occidental Mountains outside Durango, Mexico and the Pacific North West were collected for morphological and genomic analyses. In order to generate a phylogenetic inference of Arbutus, a genome skimming method was applied to target low copy loci. A Bayesian analysis will be applied to phylogenetic reconstruction and relationship analyses in the genus Arbutus. In order to answer objective two, a principle component and canonical analysis of morphological characteristics will be performed to determine if any traits are distinguishable and can be used to aid in species identification. Additionally, the software STRUCTURE will be used to help visualize the genetic structure of individuals occurring in sympatry and allopatry while MIGRATE will be applied to help measure the magnitude and direction of gene flow. By understanding species delimitations in Arbutus, we hope our result can be applied to conservation efforts of this ecologically important genus.

1 - San Diego State University, Evolutionary Biology, 5070 1/2 Niagara Ave, San Diego, CA, 92107, USA
2 - San Diego State University, Biology
3 - 1720 Avondale Drive, Roseville, CA, 95747, United States
4 - CIIDIR- Instituto Politecnico Nacional, Sigma 119, 20 de Noviembre II, Durango, Dgo, Mexico
5 - San Diego State University, 4319 Yale Ave, San Diego State University, La Mesa, CA, 91942, United States

Keywords:
Phylogenetics
population genetics
Arbutus
Madrones
Next Generation Sequencing.

Presentation Type: Colloquium Presentations
Session: CO06, Ericaceae: Systematics, Ecology and Evolution
Location: Tucson D/Starr Pass
Date: Tuesday, July 30th, 2019
Time: 8:45 AM
Number: CO06004
Abstract ID:1032
Candidate for Awards:None